Debian 5 php5 package has serious security issues as follows:

To prevent Denial of Service attacks by exhausting the number of available temporary file names, the max_file_uploads option introduced in PHP 5.3.1 has been backported.

Due to the nature of this new option a default limit has been set to 50, hoping it is sensible enough to not to cause disruptions on existing services. The value of this new limit can be changed in the php.ini file.

If you installed the php5-suhosin extension there was a limiting mechanism in place already. In this case you may want to make sure the new limit imposed by PHP itself is not smaller than suhosin’s.

1. CVE-2009-2687: DoS via malformed JPEG images with invalid offset fields (Closes: #535888)
2. CVE-2009-2626: remote memory disclosure via ini_* functions (Closes: #540605)
3. CVE-2009-3292: multiple missing checks processing exif image data
4. CVE-2009-3291: improper handling of nul character in CommonName fields of X509 certificates
5. max_file_uploads: prevent, by limiting, temporary files exhaustion DoS
6. Add an entry to debian/NEWS about the new per-request file uploads limit

How Do I Fix This Problem?

Type the following command:
# aptitude full-upgrade
Restart / reload web server:
# /etc/init.d/apache2 restart
OR
# /etc/init.d/lighttpd restart